The present invention relates to adjustable beds, and the like, and in particular to a free-engaging drive unit therefor.
Adjustable beds are well known, and are used extensively in hospitals, nursing homes, health care facilities and institutions, as well as home care applications, to assist in the care and treatment of invalids. Such adjustable beds have at least one controller shaft that is rotated axially to manipulate an associated adjustable portion of the bed, such as the bed height, head tilt, foot tilt, and other bed functions. Fully adjustable beds normally have a separate controller shaft associated with each independently adjustable portion of the bed.
Some adjustable beds, such as the unit illustrated and described in the Applicant's above-identified related application, and in the "Quick Change 3 in 1 Bed System.TM." brochure by Joerns Healthcare, Inc. as identified in the Disclosure Statement, and hereinafter collectively referred to as "Joerns modular drive bed," have a separate mattress support frame or bedspring supported by two detachable end panels. The bedspring and the end panels are interconnected by mating keeper pins and corner hooks, so that the bed can be easily assembled and disassembled without tools. This type of bed construction greatly facilitates manufacture, shipping, delivery, storage and repair.
In the Joerns modular drive bed, the manual crank units are supported on the frame, at the foot end of the bed. Manipulation of the manual crank units therefore requires that the attendant bend over or crouch to a somewhat uncomfortable position. Hence, it would be advantageous to provide a drive unit to operate the manual crank units from a more convenient height and location on the bed. Furthermore, it would also be advantageous to provide a drive unit that would automatically couple when the bed was fully assembled, and would self-adjust for any slight misalignment that might exist between the mattress support frame and the end panels.